﻿namespace Test.Radical.ChangeTracking
{
	using System;
	using System.Linq;
	using Microsoft.VisualStudio.TestTools.UnitTesting;
	using SharpTestsEx;
	using Topics.Radical.ComponentModel.ChangeTracking;
	using Topics.Radical.ChangeTracking;

	[TestClass]
	public class AtomicChangesChangeTrackingServiceTests
	{
		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_beginAtomicOperation_normal_should_create_valid_atomic_operation()
		{
			var target = new ChangeTrackingService();
			var actual = target.BeginAtomicOperation();

			actual.Should().Not.Be.Null();
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_should_set_is_changed_only_on_operation_completed()
		{
			var target = new ChangeTrackingService();

			var person = new Person( target );
			var list = new PersonCollection( target );

			using( var actual = target.BeginAtomicOperation() )
			{
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				target.IsChanged.Should().Be.False();

				actual.Complete();
			}

			target.IsChanged.Should().Be.True();
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_atomicOperation_after_operation_complete_entityState_should_be_changed()
		{
			var target = new ChangeTrackingService();

			var person = new Person( target );

			target.AcceptChanges();
			
			using( var op = target.BeginAtomicOperation() )
			{
				person.Name = "Mauro";

				op.Complete();
			}

			var state = target.GetEntityState( person );

			var actual = (state & EntityTrackingStates.HasBackwardChanges ) == EntityTrackingStates.HasBackwardChanges;
			actual.Should().Be.True();
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_should_fully_rollback_on_single_undo()
		{
			var target = new ChangeTrackingService();

			var person = new Person( target );
			var list = new PersonCollection( target );

			using( var actual = target.BeginAtomicOperation() )
			{
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				actual.Complete();
			}

			target.Undo();

			list.Count.Should().Be.EqualTo( 0 );
			person.Name.Should().Be.EqualTo( String.Empty );
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_redo_should_reapply_all_changes_with_one_pass()
		{
			var target = new ChangeTrackingService();

			var person = new Person( target );
			var list = new PersonCollection( target );

			using( var actual = target.BeginAtomicOperation() )
			{
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				actual.Complete();
			}

			target.Undo();
			target.Redo();

			list.Count.Should().Be.EqualTo( 1 );
			person.Name.Should().Be.EqualTo( "Mauro Servienti" );
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_undo_redo_should_restore_in_one_pass()
		{
			var target = new ChangeTrackingService();

			var person = new Person( target );
			var list = new PersonCollection( target );

			using( var actual = target.BeginAtomicOperation() )
			{
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				actual.Complete();
			}

			target.Undo();
			target.Redo();
			target.Undo();

			list.Count.Should().Be.EqualTo( 0 );
			person.Name.Should().Be.EqualTo( String.Empty );
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_getEntityState_should_return_valid_entity_state()
		{
			var target = new ChangeTrackingService();

			var person = new Person( target );
			var list = new PersonCollection( target );

			using( var op = target.BeginAtomicOperation() )
			{
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				op.Complete();
			}

			var actual = target.GetEntityState( person );
			actual.Should().Be.EqualTo( EntityTrackingStates.HasBackwardChanges | EntityTrackingStates.IsTransient | EntityTrackingStates.AutoRemove );
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_getEntities_should_return_all_changed_entities()
		{
			var target = new ChangeTrackingService();

			var person = new Person( target );
			var list = new PersonCollection( target );

			using( var op = target.BeginAtomicOperation() )
			{
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				op.Complete();
			}

			var actual = target.GetEntities( EntityTrackingStates.HasBackwardChanges, false );

			/*
			 * Non funziona perchè non funziona GetEntityState()
			 */

			actual.Contains( person ).Should().Be.True();
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_getEntities_should_return_all_transient_entities()
		{
			var target = new ChangeTrackingService();

			var list = new PersonCollection( target );
			var person = new Person( target, false );

			using( var op = target.BeginAtomicOperation() )
			{
				target.RegisterTransient( person );
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				op.Complete();
			}

			var actual = target.GetEntities( EntityTrackingStates.IsTransient, false );

			actual.Contains( person ).Should().Be.True();
		}

		[TestMethod]
		[TestCategory( "ChangeTracking" )]
		public void changeTrackingService_using_beginAtomicOperation_hasTransientEntities_should_return_true_even_for_entities_created_in_the_atomic_operation()
		{
			var target = new ChangeTrackingService();

			var list = new PersonCollection( target );
			var person = new Person( target, false );

			using( var op = target.BeginAtomicOperation() )
			{
				target.RegisterTransient( person );
				person.Name = "Mauro";
				list.Add( person );
				person.Name = "Mauro Servienti";

				op.Complete();
			}

			var actual = target.HasTransientEntities;

			actual.Should().Be.True();
		}
	}
}
